Selected by Generals Marshall and Eisenhower to replace Patton as commander of the fictional First US Army Group (FUSAG), General Lesley J. McNair arrived in France on July 23, 1944. He planned to spend a few days in France en route, visiting unit headquarters and Army Ground Forces troops as they prepared to conduct Operation Cobra – a major operation to break out of the challenging hedgerow terrain in Normandy. Operation Fortitude, the deception operation centered on the FUSAG headquarters, proved remarkably successful, tying down over twenty German divisions for several weeks in the vicinity of Pas de Calais, where Hitler expected a second Allied landing – divisions that otherwise would have added to German troop strength in the already difficult fighting in Normandy.

McNair arrived in France the day before General Bradley, Commander, First US Army planned to begin Operation Cobra. Lacking tactical close air support, General Bradley relied on B-24 strategic bombers and P-47 dive bombers for air support during the breakout. Bad weather on July 24 led Bradley to reschedule the attack for July 25, but many bombers had already departed their air bases before they could be notified that the mission was called off, and some dropped their payloads despite the poor visibility, with inaccurate drops causing ninety-seven American casualties, including seventeen dead.

McNair, close to the front that day, was convinced by his small travel team to remain safety in the rear the next day, but when a soldier told General McNair later that evening how much the troops appreciated seeing him at the front, he decided to go forward again on the morning of the 25th. This time the short drops were even worse, causing 600 casualties, including 100 dead.

After a tense search, and with the help of First US Army troops, McNair’s party finally found his remains near the front, identifiable by his rank insignia. Troops later found his West Point class ring nearby. Originally reported a result of German fire to avoid risk to the Fortitude deception, the US Army Press Corps admitted in August, 1944 that McNair had died of wounds caused by Allied bombing operations. Twelve days later, McNair’s wife Clare learned that their only child, Colonel Doug McNair, was killed by a sniper on Guam while serving as the chief of staff of the 77th Division.